In medical settings, liquids are often transferred, e.g., transfusions, blood transfusions, artificial dialysis, drawing blood, or the like. For transferring various liquids, a pipe-shaped tube can be used with connectors connected to the tube, and a plurality of liquids can be caused to converge or be shut off. Such connectors, in addition to being used as a coinjection tool attached in the middle of the tube to coinject another liquid medicine into the tube, are used for various applications. For example, in addition to using connectors provided with a switching valve function, they can be used as a three-way stopcock, and objected from support arms normally closed connectors that are attached to the end of a liquid medicine tube so that the supply of liquid from the liquid medicine tube is normally stopped and liquid is supplied as necessary.
Connectors are generally provided with a housing in which a channel space is formed, through which a liquid, such as liquid medicine, flows to the inside. A connection opening connected to the channel is furnished, the channel being connected to the channel space through the connection opening through which liquid medicine flows. An opening for supply of a liquid from the outside is also formed in the housing. The Luer part of a syringe is inserted into the opening and liquid medicine or the like is introduced into the channel space through the opening.
However, with an open connector not connected at the opening, that is, without a Luer part being inserted, the outside and the channel space are always connected, and liquid medicine in the channel part sometimes overflows to the outside. There is also the risk of bacteria growing in areas where liquid medicine adheres near the opening. For this reason, in recent years, closed connectors have often been used such that when a normally closed valve member is attached to the opening and no Luer part is inserted, the opening is blocked in leakproof fashion.
With closed connectors such as this, a slit is generally formed in the valve member attached to the opening, for example see Japanese Kokai Patent Application No. 2003-159336 or Japanese Kokai Patent Application No. Hei 8[1996]-206230. Then, in the normal state (Luer part not inserted, no liquid supplied), this slit is closed. On the other hand, to supply a liquid, a Luer part is inserted into the slit. Then the slit opens and the Luer part is exposed to the channel space in the housing. By injecting the liquid to be supplied from a syringe at this stage, liquid is discharged from the Luer part into the channel space and supplying of the liquid is accomplished. When supplying of liquid is completed, the Luer part is pulled from the slit. Then the slit closes again and the opening is closed.